1. Field of the Invention
The present invention relates to a solid state imaging device, which generates color pixel signals corresponding to a color filter covering the imaging device.
2. Description of the Related Art
A CMOS solid state imaging device, manufactured by using a CMOS LSI manufacturing process is known as a prior art imaging device having an XY address system.
An imaging device 10′ comprises pixels 21′, an output line 14′, vertical transmission lines 15′, and so on, as shown in FIG. 14. The vertical transmission lines 15′ pass vertically through a receiving surface of the imaging device 10′. And each vertical transmission line 15′ is connected to pixels 21′ which are vertically arranged along the vertical transmission lines 15′. The vertical transmission lines 15′ are connected to the output line 14′. Each pixel 21′ generates a pixel signal in accordance with a received light amount. The pixel signals are transferred to the output terminal of the imaging device 10′ via the vertical transmission lines 15′ and the horizontal output line 14′ in order. Finally, the pixel signals are output to an image signal processor.
Each pixel 21′ is covered by a color filter (not depicted) in order to capture a color image. A red-pixel, covered by a red color filter, generates a red pixel signal in accordance with a red component of the received light amount. A green-pixel, covered by a green color filter, generates a green pixel signal in accordance with a green component of the received light amount. A blue-pixel, covered by a blue color filter, generates a blue pixel signal in accordance with a blue component of the received light amount. A white balance process is carried out on the pixel signals in order to display an accurate color image. In the white balance process, each pixel signal is amplified by an adequate gain. The adequate gains for the red, green and blue pixel signals are different from each other.
Prior art imaging devices output red, green, and blue pixel signals through a single output terminal. So, a pixel-gain-amplifier, that can quickly change a gain in accordance with the color of the pixel signal to be amplified, is required.